From 51849dbdf28e558522529c0ce04ffe7b783cb393 Mon Sep 17 00:00:00 2001
From: Tagir Valeev <tagir.valeev@jetbrains.com>
Date: Fri, 17 Nov 2023 10:48:43 +0100
Subject: [PATCH] [java-inspections] SimplifyBooleanExpressionFix: retarget to
 existing pattern variable (IDEA-336123)

GitOrigin-RevId: c3e7f12fb11926084fa8a71467394635d1cfc5d9
---
 .../SimplifyBooleanExpressionFix.java         | 59 +++++++++++--------
 .../afterPatternRetargetAnotherPattern.java   | 11 ++++
 .../beforePatternRetargetAnotherPattern.java  | 11 ++++
 3 files changed, 58 insertions(+), 23 deletions(-)
 create mode 100644 java/java-tests/testData/codeInsight/daemonCodeAnalyzer/quickFix/unwrapIfStatement/afterPatternRetargetAnotherPattern.java
 create mode 100644 java/java-tests/testData/codeInsight/daemonCodeAnalyzer/quickFix/unwrapIfStatement/beforePatternRetargetAnotherPattern.java

diff --git a/java/java-impl/src/com/intellij/codeInsight/daemon/impl/quickfix/SimplifyBooleanExpressionFix.java b/java/java-impl/src/com/intellij/codeInsight/daemon/impl/quickfix/SimplifyBooleanExpressionFix.java
index 5f8b4b275dc7..b860facd8fcb 100644
--- a/java/java-impl/src/com/intellij/codeInsight/daemon/impl/quickfix/SimplifyBooleanExpressionFix.java
+++ b/java/java-impl/src/com/intellij/codeInsight/daemon/impl/quickfix/SimplifyBooleanExpressionFix.java
@@ -209,30 +209,43 @@ public class SimplifyBooleanExpressionFix extends PsiUpdateModCommandAction<PsiE
   private static void processPatternVariables(@NotNull PsiExpression subExpression) {
     List<PsiPatternVariable> variables = JavaPsiPatternUtil.getExposedPatternVariables(subExpression);
     for (PsiPatternVariable variable : variables) {
-      List<PsiReferenceExpression> refs = VariableAccessUtils.getVariableReferences(variable, variable.getDeclarationScope());
-      if (!refs.isEmpty()) {
-        PsiInstanceOfExpression target = newTargetForPatternVariable(subExpression, variable);
-        if (target != null) {
-          PsiInstanceOfExpression updated = (PsiInstanceOfExpression)JavaPsiFacade.getElementFactory(subExpression.getProject())
-            .createExpressionFromText("x instanceof T t", target);
-          updated.getOperand().replace(target.getOperand());
-          PsiTypeTestPattern newPattern = (PsiTypeTestPattern)Objects.requireNonNull(updated.getPattern());
-          PsiTypeElement checkType = target.getCheckType();
-          if (checkType == null) continue;
-          Objects.requireNonNull(newPattern.getCheckType()).replace(checkType);
-          PsiPatternVariable newVariable = (PsiPatternVariable)Objects.requireNonNull(newPattern.getPatternVariable()).replace(variable);
-          variable.delete();
-          String name = new VariableNameGenerator(target, VariableKind.LOCAL_VARIABLE).byName(variable.getName())
-            .generate(true);
-          if (!name.equals(newVariable.getName())) {
-            newVariable.setName(name);
-            for (PsiReferenceExpression ref : refs) {
-              if (ref.isValid()) {
-                ref.handleElementRename(name);
-              }
-            }
+      retargetPatternVariable(subExpression, variable);
+    }
+  }
+
+  private static void retargetPatternVariable(@NotNull PsiExpression subExpression, @NotNull PsiPatternVariable variable) {
+    List<PsiReferenceExpression> refs = VariableAccessUtils.getVariableReferences(variable, variable.getDeclarationScope());
+    if (refs.isEmpty()) return;
+    PsiInstanceOfExpression target = newTargetForPatternVariable(subExpression, variable);
+    if (target == null) return;
+    if (target.getPattern() instanceof PsiTypeTestPattern existingPattern) {
+      PsiPatternVariable existingVar = existingPattern.getPatternVariable();
+      if (existingVar != null) {
+        for (PsiReferenceExpression ref : refs) {
+          if (ref.isValid()) {
+            ref.handleElementRename(existingVar.getName());
           }
-          target.replace(updated);
+        }
+        return;
+      }
+    }
+    PsiInstanceOfExpression updated = (PsiInstanceOfExpression)JavaPsiFacade.getElementFactory(subExpression.getProject())
+      .createExpressionFromText("x instanceof T t", target);
+    updated.getOperand().replace(target.getOperand());
+    PsiTypeTestPattern newPattern = (PsiTypeTestPattern)Objects.requireNonNull(updated.getPattern());
+    PsiTypeElement checkType = target.getCheckType();
+    if (checkType == null) return;
+    Objects.requireNonNull(newPattern.getCheckType()).replace(checkType);
+    PsiPatternVariable newVariable = (PsiPatternVariable)Objects.requireNonNull(newPattern.getPatternVariable()).replace(variable);
+    variable.delete();
+    target.replace(updated);
+    String name = new VariableNameGenerator(target, VariableKind.LOCAL_VARIABLE).byName(variable.getName())
+      .generate(true);
+    if (!name.equals(newVariable.getName())) {
+      newVariable.setName(name);
+      for (PsiReferenceExpression ref : refs) {
+        if (ref.isValid()) {
+          ref.handleElementRename(name);
         }
       }
     }
diff --git a/java/java-tests/testData/codeInsight/daemonCodeAnalyzer/quickFix/unwrapIfStatement/afterPatternRetargetAnotherPattern.java b/java/java-tests/testData/codeInsight/daemonCodeAnalyzer/quickFix/unwrapIfStatement/afterPatternRetargetAnotherPattern.java
new file mode 100644
index 000000000000..5b69b9833a36
--- /dev/null
+++ b/java/java-tests/testData/codeInsight/daemonCodeAnalyzer/quickFix/unwrapIfStatement/afterPatternRetargetAnotherPattern.java
@@ -0,0 +1,11 @@
+// "Simplify 'obj instanceof String str' to true" "true"
+class Test {
+  void test(Object obj) {
+    if (obj instanceof String s) {
+      if (s.isEmpty()) {
+
+      }
+      System.out.println(s);
+    }
+  }
+}
\ No newline at end of file
diff --git a/java/java-tests/testData/codeInsight/daemonCodeAnalyzer/quickFix/unwrapIfStatement/beforePatternRetargetAnotherPattern.java b/java/java-tests/testData/codeInsight/daemonCodeAnalyzer/quickFix/unwrapIfStatement/beforePatternRetargetAnotherPattern.java
new file mode 100644
index 000000000000..2c2236a8c3c8
--- /dev/null
+++ b/java/java-tests/testData/codeInsight/daemonCodeAnalyzer/quickFix/unwrapIfStatement/beforePatternRetargetAnotherPattern.java
@@ -0,0 +1,11 @@
+// "Simplify 'obj instanceof String str' to true" "true"
+class Test {
+  void test(Object obj) {
+    if (obj instanceof String s) {
+      if (obj instanceof<caret> String str && str.isEmpty()) {
+
+      }
+      System.out.println(s);
+    }
+  }
+}
\ No newline at end of file